JP7379863B2 - Microwave packaging bag - Google Patents

Description

The present invention makes it possible to heat the contents in a sealed package, and prevents the packaging bag from bursting due to the steam generated when heating in a microwave oven. This relates to a packaging bag for a microwave oven that can automatically release air to the outside, reduce internal pressure, and allow cooking.

Traditionally, cooked or semi-cooked foods such as meat buns, red bean paste buns, shumai, gyoza, hamburgers, hot dogs, spaghetti, fried noodles, fried udon noodles, cooked noodles such as rice noodles, etc., have been stored in plastic packaging bags. There are packaged foods on the market that are cooked in a microwave oven before consumption. In addition, cooked or semi-cooked liquid, viscous, or mixed liquid and solid contents, such as curry, stew, soup, etc., can be stored in plastic packaging bags and microwaved before eating. There are many packaged foods on the market that are cooked by heating. Recently, when the packaging bags used to store such foods are heated in a microwave oven, the internal pressure inside the packaging bag increases due to the steam generated from the food and the thermal expansion of the internal air, causing the packaging bag to burst. Many packaging bags are used in which various steam release means are formed on the packaging bag to provide convenience to the user (for example, see Patent Document 1).

Patent Document 1 discloses a packaging in which a laminate strength adjustment layer is provided as a means for easy vaporization in the lower heat-bonded part of the gusset part, which is shorter in distance from the folded part, and this part becomes a wing part, and the package is filled with contents. Even if the bag is heated in a microwave oven with the wing section facing upward while the bag is still sealed, the packaging bag will be automatically opened by the easy steaming means provided in the wing section without causing the bag to break due to the steam generated by heating. Since the part is formed in the upper part of the packaging bag, it is an excellent packaging bag that can be heated as it is without the contents spilling out.

However, in Patent Document 1, a gusset forming member folded into a substantially V-shape at a folded portion is positioned between the front and rear wall members, and both edges in a direction perpendicular to the folded portion are joined by a side edge thermal bonding portion. Therefore, if the packaging bag expands and internal pressure is applied to the intersection of the folded part of the gusset forming member and the side edge heat-adhesive part due to heating due to moisture in the contents, the seal in that part may recede or in severe cases. However, there is a problem in that it causes the packaging bag to break.

Japanese Patent Application Publication No. 2007-223626

Therefore, the present invention has been made to solve the above problem, and its purpose is to solve the problem of the gas inside the packaging bag that is generated when the contents of food, etc. are heated in a microwave oven while they are still sealed. To provide a packaging bag for a microwave oven, which can automatically discharge internal pressure increased by steam etc. to the outside of the packaging bag, prevent the bag from breaking due to lowering the internal pressure, and allow safe heating and cooking.

In order to achieve the above-mentioned object, the present invention provides a packaging bag for a microwave oven according to the present invention as set forth in claim 1. In a microwave packaging bag used for a package in which an opening is formed toward the top of the package and steam is dissipated from the opening to prevent the bag from tearing, the first upper member and the first surface are connected to each other through the bent portion. and a second upper member partitioned into a second surface, and a lower member, the first upper member and the lower member being bent in a V-shape in cross section at the bending portion. A wing portion is formed between the members, the first surface facing the first upper member, and the peripheral edge excluding the bent portion being joined at a wing joint portion, excluding the second surface and the wing portion. A packaging bag for a microwave oven in which the first upper member faces the lower member and has a peripheral edge joined at a peripheral edge joint, the bag comprising an easy-to-vaporize means for forming the opening in the wing part, The first upper member and the lower member are joined at positions sandwiching the bent portion from the inner edges of the peripheral edge joint portions on both sides that intersect with the bent portion, and the first protruding joint portion and the second upper portion are protruded inwardly. The second surface of the member and the lower member are joined to each other and includes a second protruding joint portion that protrudes inward.

Further, the present invention as set forth in claim 2 provides the packaging bag for a microwave oven as set forth in claim 1, wherein a third protrusion protrudes inward from an inner edge of the wing joint portion of the wing portion to a position near the folded portion. It is characterized by having a joint part.

The packaging bag for microwave ovens of the present invention automatically removes the internal pressure that increases due to the steam inside the packaging bag generated by heating when the contents, such as food, are cooked in a microwave oven while the contents are sealed. By lowering the internal pressure, the bag will not break and cooking can be done safely.

FIG. 1 is a perspective view showing a first embodiment of a packaging bag for a microwave oven according to the present invention. FIG. 2 is an exploded perspective view of FIG. 1; FIG. 1 is a plan view showing a first embodiment of a packaging bag for a microwave oven according to the present invention. It is a back view showing a first embodiment of a packaging bag for a microwave oven according to the present invention. 5 is an enlarged view within the broken line in FIG. 4. FIG. It is a top view which shows other embodiment of the packaging bag for microwave ovens based on this invention. It is an explanatory view showing an example of composition of a laminate of a packaging bag for a microwave oven according to the present invention. It is an explanatory view showing an opening state.

The present invention described above will be described in detail below using drawings and the like.
FIG. 1 is a perspective view showing a first embodiment of a packaging bag for a microwave oven according to the present invention, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is a perspective view showing a first embodiment of a packaging bag for a microwave oven according to the present invention. FIG. 4 is a rear view showing the first embodiment of the microwave packaging bag according to the present invention, FIG. 5 is an enlarged view within the broken line in FIG. 4, and FIG. 6 is a microwave packaging bag according to the present invention. FIG. 7 is an explanatory view showing an example of the structure of the laminate of the microwave packaging bag according to the present invention, and FIG. 8 is an explanatory view showing an open state. 1' is a microwave packaging bag, 2 is a peripheral joint, 2u is a top joint, 2s is a side joint, 2d is a bottom joint, 3 is a first protruding joint, 4 is a second protruding joint, 5 is a third protruding joint, 6 is an opening, 7 is a content, 10 is a first upper member, 20 is a second upper member, 21 is a first surface, 22 is a second surface, 23 is a bent portion, 30 40 is a lower member, 40 is a wing portion, 41 is an easy-to-vaporize means, 42 is a wing joint portion, 50 is a laminate, 51 is a base material layer, 52 is a printed layer, 53 is an adhesive layer, and 54 is a heat-fusible resin In the layer, a indicates the left and right length, b indicates the top and bottom length, and c indicates the interval.

FIG. 1 is a perspective view showing a first embodiment of a packaging bag for a microwave oven according to the present invention, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is a perspective view showing a first embodiment of a packaging bag for a microwave oven according to the present invention. FIG. 4 is a rear view showing the first embodiment of the microwave packaging bag according to the present invention. The microwave packaging bag 1 according to the first embodiment of the present invention is capable of generating electricity when heating a package formed by filling the microwave packaging bag 1 with the contents 7 (see FIG. 8) in a microwave oven. An opening 6 (see FIG. 8) is automatically formed toward the top of the package by steam, and the steam is dissipated from the opening 6 to prevent the package from tearing. As shown in FIGS. 1 and 2, the microwave packaging bag 1 includes a rectangular first upper member 10, a second upper member 20, and a lower member 30. The second upper member 20 is divided into a first surface 21 and a second surface 22 via a bent portion 23, and the length of the second surface 22 in the direction perpendicular to the bent portion 23 is longer than the length of the first surface 21. The length of has been shortened. Further, the first upper member 10, the second upper member 20, and the lower member 30 have the same width, but different lengths, and the length of the first upper member 10 is shorter than the length of the lower member 30. .

As shown in FIGS. 1 and 2, the second upper member 20 is arranged between the first upper member 10 and the lower member 30 in a state where it is bent in a V-shape in cross section at the bending part 23, and the first surface 21 is 1. A peripheral edge facing the upper member 10 excluding the bent portion 23 is joined at a wing joint portion 42 to form a wing portion 40. The first upper member 10 excluding the second surface 22 and the wing portion 40 faces the lower member 30 and is joined at the peripheral edge by the peripheral edge joint 2, forming an upper end joint 2u, a side end joint 2s, and a lower end joint 2d. ing. The lower end joint portion 2d is not joined and left open before filling with the contents, and after the contents are filled through the opening, the lower end joint portion 2d is joined to form a hermetically sealed package.

Note that, as will be described later, the first upper member 10, the second upper member 20, and the lower member 30 are a laminate 50 (see FIG. 6) that includes a heat-fusible resin layer 54 (see FIG. 6) at least in the innermost layer. is used, and the surfaces of the heat-fusible resin layers 54 of each laminate 50 are made to face each other and bonded by thermal bonding.

As shown in FIGS. 1 and 3, the wing portion 40 is provided with an easy-to-vaporize means 41 in the center portion in the left-right direction. The easy-to-vaporize means 41 is a means that automatically forms an opening 6 (see FIG. 8) due to the increased internal pressure caused by the steam generated when a package filled with contents is heated in a microwave oven. . The first surface 21 of the second upper member 20 faces the first upper member 10, and the peripheral edges of both end portions and the tip portion excluding the bent portion 23 are joined by thermal bonding at a boat-shaped wing joint portion 42, Near the center of the tip, the joining length from the side of the folded portion 23 of the wing joint 42 to the outer edge of the tip is the shortest. This part is the easy vaporization means 41, and as will be described later, the seal of the wing joint 42 starts to retreat due to internal pressure, and the joint length from the bent part 23 side to the outer edge of the tip is the shortest. The bonded state of the bonded portion is first released, the opening 6 is formed, and the steam is dissipated, thereby preventing the microwave packaging bag 1 from breaking. Although the example in which the joint length at the center of the tip of the wing joint portion 42 of the wing portion 40 is shorter than the length of the other joint portions as the easy vaporization means 41 has been shown, the wing joint portion 42 is not limited to this. It is possible to use a known means for facilitating vaporization, in which the unjoined part is surrounded by a narrow joined part in the section 40, and a slit, a hole, etc. is provided in the surrounded unjoined part area.

As shown in FIGS. 1, 3, and 4, the first upper member 10 and the lower member 30 are joined from the inner edges of the side end joints 2s, which are the peripheral joints 2 on both sides that intersect with the bent portion 23 of the second upper member 20. First protruding joint portions 3 protruding inward are provided along and in the vicinity of the bent portions 23, respectively. As shown in FIG. 4, the second surface 22 of the second upper member 20 and the lower member 30 are connected from the inner edge of the side edge joint portions 2s, which are the peripheral edge joint portions 2 on both sides intersecting the bent portion 23 of the second upper member 20. Second protruding joint portions 4 that are joined and protrude inward are provided along and in the vicinity of the bent portions 23, respectively. The wing portion 40 does not include any protruding joints. Further, the first protruding joint portion 3 and the second protruding joint portion 4 are provided at positions sandwiching the bent portion 23 .

FIG. 5 is an enlarged view of the portion shown in the circle in FIG. 4, and shows the configuration of the first protruding joint portion 3 and the second protruding joint portion 4. As shown in FIG. As shown in FIG. 5, the first protruding joint part 3 and the second protruding joint part 4 have a left-right length a in the direction along the bending part 23 from the inner edge of the side end joint part 2s, which is 3 mm or more and 10 mm or less. preferable. The vertical length b in the direction in which the upper end joint 2u and the lower end joint 2d face each other is about 3 to 10 mm. The vertical distance c between the first protruding joint part 3 and the second protruding joint part 4 sandwiching the bent part 23 is preferably within 4 mm, that is, within ±2 mm with respect to the bent part 23. Further, it is more preferable that the first protruding joint part 3 and the second protruding joint part 4 are arranged line-symmetrically with respect to the bending part 23. By configuring the first protruding joint part 3 and the second protruding joint part 4 as described above, the influence of internal pressure generated by microwave oven heating applied to the intersection point P between the bending part 23 and the side end joint part 2s is alleviated. , the microwave oven packaging bag 1 will not be torn.

Next, the easy vaporization means 41 will be explained with reference to FIG. FIG. 8 shows a state in which steam is dissipated by heating when a package in which the contents 7 are filled in the microwave packaging bag 1 of the present invention is heated in a microwave oven, and the position corresponds to the cross section taken along the line AA in FIG. 3. FIG. When the package is placed in a microwave oven with the wing part 40 facing upward and cooked, the seal of the wing joint part 42 begins to retreat due to the internal pressure that increases due to the steam inside the microwave packaging bag 1 generated by heating. , the bonded state of the wing joint portion 42 equipped with the easy-to-vaporize means 41 having the shortest joint length from the side of the bent portion 23 to the outer edge of the tip portion is automatically released, and the opening portion 6 is formed. As the steam is dissipated, the internal pressure is discharged and the internal pressure is lowered, so that the packaging bag 1 for microwave oven does not break. When the internal pressure increases due to this heating, in the conventional microwave packaging bag with wing parts, the part where the first upper member 10, the second upper member 20, and the lower member 30 are joined, that is, the second upper member 20 If internal pressure is applied to the intersection point P between the bent portion 23 and the side end joint portions 2s of both edges in the direction orthogonal to the folded portion 23, it may cause the seal to recede at that portion or, in severe cases, cause the microwave oven packaging bag 1 to break. However, by providing the first protruding joint part 3 and the second protruding joint part 4 at positions sandwiching the bent part 23, the influence of internal pressure applied to the intersection part P is alleviated, and the microwave packaging bag 1 is prevented from breaking. This has the effect of not bagging. Further, the length of the first upper member 10 is shorter than the length of the lower member 30, and the length of the second upper member 20 in the direction perpendicular to the bent portion 23 of the first surface 21 and the second surface 22 is the length of the second surface. By configuring the length of the first surface 21 to be shorter than the length of the wing part 22, when the internal pressure increases, the wing part 40 turns upward and the opening part 6 is formed at the top of the wing part 40, so that after cooking, The package can be safely removed from the microwave oven.

FIG. 6 is a plan view showing another embodiment of the packaging bag for a microwave oven according to the present invention. As shown in FIG. 6, the microwave packaging bag 1' has a third protruding joint portion 5 that protrudes inward from the inner edge of the wing joint portion 42 of the wing portion 40 to a position near the bent portion 23 along the bent portion 23. are provided on both the left and right sides. The size and arrangement position of the third protruding joint part 5 are similar to those of the second protruding joint part 4. By providing the third protruding joint portion 5, the microwave packaging bag 1' is less likely to break when heated in a microwave oven, which is more preferable. The rest is the same as the first embodiment, is given the same reference numeral, and the explanation is omitted.

Next, a configuration example of the laminate 50 forming the microwave packaging bag of the present invention will be described with reference to FIG. 7. As shown in FIG. 7, the laminate 50 has a structure including a base material layer 51, a printing layer 52, an adhesive layer 53, and a heat-fusible resin layer 54 in this order. Note that an intermediate layer (not shown) may be provided between the base material layer 51 and the heat-fusible resin layer 54 in consideration of the sterilization conditions of the contents and the package, the transportation conditions of the package, and the like.

The base material layer 51 is not particularly limited as long as it is made of a material that has heat resistance and can normally withstand heating in a microwave oven. For example, any one of stretched polyethylene terephthalate film, silica-deposited stretched polyethylene terephthalate film, alumina-deposited stretched polyethylene terephthalate film, stretched nylon film, silica-deposited stretched nylon film, alumina-deposited stretched nylon film, etc., or a lamination of two or more of these. Composite films can be used. Further, the thickness of the base material layer 51 is about 9 μm to 50 μm, preferably about 9 μm to 30 μm.

As the intermediate layer, the film shown in the base layer 51, an ethylene-vinyl alcohol copolymer film, or the like is used.

Moreover, the resin constituting the heat-fusible resin layer 54 can generally be used as long as it can withstand heating in a microwave oven. For example, low density polyethylene, linear low density polyethylene, medium density polyethylene, high density polyethylene, polypropylene, propylene-ethylene copolymer, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid Resins such as copolymers, ethylene-methyl acrylate copolymers, ethylene-ethyl acrylate copolymers, ethylene-methyl methacrylate copolymers, or ionomers can be used.

The heat-fusible resin layer 54 may be formed of these resins by an extrusion lamination method, or may be a film formed in advance by a T-die method, an inflation method, or the like. The thickness of the heat-fusible resin layer 54 is preferably about 20 μm to 100 μm.

Next, the base material layer 51, the heat-fusible resin layer 54, the base material layer 51, the intermediate layer, and the heat-fusible resin layer 54 are laminated by a normal lamination method such as an extrusion lamination method or a dry lamination method. be done. The adhesive layer 53 is an adhesive resin layer such as a polyolefin resin used in an extrusion lamination method, or an adhesive layer such as a urethane-based two-component reactive adhesive used in a dry lamination method.

The present invention will be further explained below with reference to Examples.

[Example 1]
A biaxially stretched nylon film (ON) with a thickness of 15 μm is used as the base material layer 51, and gravure printing is performed on one side of the base material layer 51, and a printed layer 52 is provided with a steam vent display, handling precautions, design, etc. printed thereon. Next, using linear low density polyethylene (LLDPE) with a thickness of 60 μm as the heat-fusible resin layer 54, a dry lamination method ( DL) to produce a laminate 50 of ON 15 μm/printed layer/DL/LLDPE 60 μm to form the first upper member 10 and the lower member 30. In the second upper member 20, LLDPE having a thickness of 30 μm was used for the heat-fusible resin layer 54, and the layers were similarly laminated by the dry lamination method to obtain a laminate 50 having a configuration of ON 15 μm/printed layer/DL/LLDPE 30 μm. Using these laminates 50, the surfaces of the heat-fusible resin layers 54 were made to face each other and sealed to produce a bag with the lower end joint 2d of the microwave oven packaging bag 1 shown in FIG. 1 as an unsealed opening. . The dimensions were as follows.
Top and bottom external dimensions: 180mm
Left and right outer dimensions: 140mm
Vertical dimension of first upper member: 160mm
Length from the outer edge of the lower end joint to the bent part: 135mm
Wing part (first side) top and bottom dimensions: 25mm
Shape of wing joint: Boat shape Top and bottom seal width of easy vaporization part: 5mm (center bottom of boat shape)
Dimensions of the first protruding joint and the second protruding joint:
a: 3mm
b: 5mm
c: 3mm
Peripheral joint seal width: 10mm

[Example 2]
A bag was produced in which the lower end joint part 2d of the packaging bag 1' for a microwave oven shown in FIG. 5 was provided with the third protruding joint part 5 on the wing part 40 and was an unsealed opening. The rest was the same as in Example 1. The size and position of the third protruding joint were the same as those of the first and second protruding joints.

After filling tap water through the openings of the microwave packaging bag 1 and the microwave packaging bag 1' produced in Examples 1 and 2, the bags were sealed with a seal width of 10 mm at the lower end joint to produce a package.
When the package was placed in a microwave oven with the wing section facing upward and heated in a microwave oven with an output of 500 W, the package was opened from the easy-to-vaporize means 41 provided in the wing section 40 after about 2 minutes, and steam and water rose. The internal pressure could be quickly discharged to the outside. Further, when the intersection point P of the wing portion 40 where the bent portion 23 and the side end joint portion 2s intersect was observed, no seal regression was observed and no abnormality was observed.

1, 1' Microwave oven packaging bag 2 Peripheral joint 2u Upper joint 2s Side joint 2d Lower joint 3 First protruding joint 4 Second protruding joint 5 Third protruding joint 6 Opening 7 Contents 10 First upper member 20 Second upper member 21 First surface 22 Second surface 23 Bend portion 30 Lower member 40 Wing portion 41 Easy vaporization means 42 Wing joint portion 50 Laminated body 51 Base material layer 52 Print layer 53 Adhesive layer 54 Heat-fusible resin layer a Left and right length b Top and bottom length c Interval P Intersection part

Claims (2)

a first upper member;
a second upper member partitioned into a first surface and a second surface via a bent portion;
A lower member;
The second upper member is arranged between the first upper member and the lower member in a state where the second upper member is bent in a V-shape in cross-sectional view at the bending portion, and the first surface faces the first upper member and the A wing part is formed in which the periphery excluding the bent part is joined at the wing joint part,
A packaging bag for a microwave oven, wherein the first upper member excluding the second surface and the wing portion faces the lower member and has a peripheral edge joined at a peripheral edge joint portion,
comprising an easy-to-vaporize means for forming the opening in the wing part,
The first upper member and the lower member are joined at positions sandwiching the bent portion from the inner edges of the peripheral edge joint portions on both sides that intersect with the bent portion, and the first protruding joint portion and the second upper portion are protruded inwardly. a second protruding joint portion that joins the second surface of the member and the lower member and protrudes inward;
The length of the first protruding joint part and the second protruding joint part in the direction from the inner edge of the peripheral joint part to the bending part is 3 mm or more and 10 mm or less,
A packaging bag for a microwave oven, comprising a third protruding joint part that projects inward from an inner edge of the wing joint part of the wing part at a position near the folded part. The first protruding joint part and the second protruding joint part are located apart from the bent part,
2. The electronic device according to claim 1, wherein the second protruding joint portion and the third protruding joint portion are located in an overlapping position when the second members are overlapped with each other by tilting the wing portion toward the upper end side. Microwave packaging bag.

Images